Drug‐resistant parietal epilepsy: polymorphic ictal semiology does not preclude good post‐surgical outcome

We investigated the anatomo‐electro‐clinical features and clinical outcome of surgical resections strictly confined to the parietal lobe in 40 consecutive patients who received surgery for pharmacoresistant seizures. The population was subcategorized into a paediatric (11 subjects; mean age at surgery: 7.2+/?3.7 years) and an adult group (29 patients; mean age at surgery: 30+/?10.8 years). The paediatric group more frequently exhibited personal antecedents, neurological impairment, high seizure frequency, and dysplastic lesions. Nonetheless, compared with adults, children had better outcome and more frequently reached definitive drug discontinuation after surgery. After a mean follow‐up of 9.4 years (range: 3.1–16.7), 30 subjects (75%) were classified as Engel Class I. The presence of multiple types of aura in the same patient, as well as a high incidence of secondary generalization, represented a characteristic feature of parietal seizures and did not correlate negatively with surgical outcome. A total resection of the epileptogenic zone and a localizing/regional interictal EEG were statistically significant predictive factors of outcome. Intracerebral investigation, performed in 55% of cases, contributed to complete tailored resections of the epileptogenic area and determination of prognosis. Frequent subjective manifestations of parietal lobe seizures, such as vertiginous, cephalic and visual‐moving sensations, underscore their potential misdiagnosis as non‐epileptic events.     

Identification of Frontal Lobe Epileptic Foci in Children Using Positron Emission Tomography

Summary: Purpose: Presurgical evaluation for intractable frontal lobe epilepsy (FLE) is difficult and invasive, partly because anatomic neuroimaging studies with computed tomography (CT) and magnetic resonance imaging (MRI) typically do not show a discrete lesion. In adult patients with FLE, functional neuroimaging of glucose metabolism with positron emission tomography (PET) is less sensitive in detecting focal metabolic abnormalities than in temporal lobe epilepsy (TLE). Comparable data on children with FLE are not available. Methods: We used high-resolution PET scanning of glucose metabolism to evaluate 13 children (age 17 months to 17 years; mean age 9.5 years) with intractable FLE being considered for surgical treatment. Only children with normal CT and MRI scans were included. Results: Hypometabolism including the frontal lobe was evident in 12 of the 13 children, was unilateral in 11 of 13, and was restricted to the frontal lobe in 8 of 13. One child showed bilateral frontal cortex hypometabolism and another had anictal PET scan demonstrating unilateral frontal cortex hyper-metabolism surrounded by hypometabolism. Additional hypo–metabolic areas outside the frontal cortex were observed in 5 children in parietal and/or temporal cortex. Localization of seizure onset on scalp EEG was available in 10 children and corresponded to the location of frontal lobe PET abnormality in 8. However, in 4 of the 10 children, the extent of hypometabolism exceeded the epileptogenic region indicated by ictal EEG. In 2 of the 13 children, the abnormality evident on EEG was more extensive than that evident on PET. In the remaining 3 children for whom only interictal EEG data were available, the PET foci did not correspond in location to the interictal EEG abnormalities. In 11 of the 13 children, the presumed region of seizure onset in the frontal lobe, as based on analysis of seizure semiology, corresponded to the locations of frontal lobe glucose metabolism abnormalities. Conclusions: Although high-resolution PET appears to be very sensitive in localizing frontal lobe glucose metabolic abnormalities in children with intractable FLE and normal CT/ MRI scans, the significance of extrafrontal metabolic disturbances requires further study; these may represent additional epileptogenic areas, effects of diaschisis, seizure propagation sites, or secondary epileptogenic foci.     

Widespread cortical thinning in children with frontal lobe epilepsy

Purpose: Spread of seizure activity outside the frontal lobe due to cortico‐cortical connections can result in alteration in the cortex beyond the frontal lobe in children with intractable frontal lobe epilepsy (FLE). The aim of this study was to identify regions of reduced cortical thickness in children with intractable FLE. Methods: High‐resolution volumetric T₁‐weighted imaging was performed on 17 children with FLE, who were being evaluated for epilepsy surgery, and 26 age‐matched healthy controls. The cortical thickness of 12 patients with left FLE and 5 patients with right FLE was compared to controls. The clusters of cortical thinning were regressed against age of seizure onset, duration of epilepsy, seizure frequency, and number of medications. Key Findings: In children with left FLE, cortical thinning was present in the left superior frontal, paracentral, precuneus, cingulate, inferior parietal, supramarginal, postcentral, and superior temporal gyri, as well as in the right superior and middle frontal, medial orbitofrontal, supramarginal, postcentral, banks of superior temporal sulcus, and parahippocampal gyri. In children with right FLE, cortical thinning was present in the right precentral, postcentral, transverse temporal, parahippocampal, lingual, and lateral occipital gyri, as well as in the left superior frontal, inferior parietal, postcentral, superior temporal, posterior cingulate, and lingual gyri. In children with left FLE, following exclusion of one outlier, there was no significant association between age at seizure onset, duration of epilepsy, seizure frequency and number of medications with clusters of cortical thinning. In children with right FLE, age at seizure onset, duration of epilepsy, frequency of seizures, and number of medications were not associated with clusters of cortical thinning within the right and left hemispheres. Significance: Cortical changes were present in the frontal and extrafrontal cortex in children with intractable FLE. These changes may be related to spread of seizure activity, large epileptogenic zones involving both frontal and extrafrontal lobes, and development of secondary epileptogenic zones that over time lead to cortical abnormality. Further studies correlating cortical changes with neurocognitive measures are needed to determine if the cortical changes relate to cognitive function.     

Drug‐resistant parietal lobe epilepsy: clinical manifestations and surgery outcome

Aim. We reviewed a large surgical cohort to investigate the clinical manifestations, EEG and neuroimaging findings, and postoperative seizure outcome in patients with drug‐resistant parietal lobe epilepsy (PLE). Methods. All drug‐resistant PLE patients, who were investigated for epilepsy surgery at Jefferson Comprehensive Epilepsy Center between 1986 and 2015, were identified. Demographic data, seizure data, EEG recordings, brain MRI, pathological findings, and postsurgical seizure outcome were reviewed. Results. In total, 18 patients (11 males and seven females) were identified. Sixteen patients (88%) had tonic‐clonic seizures, 12 (66%) had focal seizures with impaired awareness, and 13 (72%) described auras. Among 15 patients who had brain MRI, 14 patients (93%) had parietal lobe lesions. Only three of 15 patients (20%) who had interictal scalp EEG recordings showed parietal interictal spikes. Of 12 patients with available ictal surface EEG recordings, only three patients (25%) had parietal ictal EEG onset. After a mean follow‐up duration of 8.6 years, 14 patients (77.7%) showed a favourable postoperative seizure outcome. Conclusion. In patients with PLE, semiology and EEG may be misleading and brain MRI is the most valuable tool to localize the epileptogenic zone. Postsurgical seizure outcome was favourable in our patients with drug‐resistant parietal lobe epilepsy.     

Posterior quadrantic epilepsy surgery: technical variants, surgical anatomy, and case series

OBJECTIVE: Patients with intractable epilepsy due to extensive lesions involving the posterior quadrant (temporal, parietal, and occipital lobes) form a small subset of epilepsy surgery. This study was done with a view to analyze our experience with this group of patients and to define the changes in the surgical technique over the last 15 years. We also describe the microsurgical technique of the different surgical variants used, along with their functional neuroanatomy. METHODS: In this series there were 13 patients with a median age of 17 years. All patients had extensive presurgical evaluation that provided concordant evidence localizing the lesion and seizure focus to the posterior quadrant. The objective of the surgery was to eliminate the effect of the epileptogenic tissue and preserve motor and sensory functions. RESULTS: During the course of this study period of 15 years, the surgical procedure performed evolved toward incorporating more techniques of disconnection and minimizing resection. Three technical variants were thus utilized in this series, namely, (i) anatomical posterior quadrantectomy (APQ), (ii) functional posterior quadrantectomy (FPQ), and (iii) periinsular posterior quadrantectomy (PIPQ). After a median follow-up period of 6 years, 12/13 patients had Engel's Class I seizure outcome. CONCLUSION: The results of surgery for posterior quadrantic epilepsy have yielded excellent seizure outcomes in 92% of the patients in the series with no mortality or major morbidity. The incorporation of disconnective techniques in multilobar surgery has maintained the excellent results obtained earlier with resective surgery.     

Epilepsy surgery in children: results and predictors of outcome on seizures

PURPOSE: To retrospectively analyze the results on seizures of surgery in children with drug-resistant focal epilepsy. To identify the factors predicting seizure control among several presurgical, surgical, and postsurgical variables. METHODS: One hundred thirteen patients (67 male, 46 female), younger than 16 years, operated on from 1996 to 2004 and followed-up for at least 2 years were identified. Individualized microsurgical resections, aimed at removal of the epileptogenic zone, were performed according to the results of tailored presurgical evaluations, which included stereo-electroencephalographic recording with intracerebral electrodes when needed. Risk of seizure recurrence was assessed for the considered variables by bivariate and multivariate analysis. RESULTS: Mean age at surgery was 8.8 years, mean duration of epilepsy was 5.7 years, and mean age at seizure onset was 3.1 years. One hundred eight patients (96%) had an abnormal magnetic resonance imaging. At postoperative follow-up (mean duration 55.1 month), 77 patients (68%) were in Engel's class I, with 68 patients (60%) being seizure free (Engel's classes Ia and Ic). At multivariate analysis, variables associated with a significantly lower risk of seizure recurrence were unifocal lesion at MRI and older age at seizure onset (presurgical variables), temporal unilobar resection and complete lesionectomy (surgical variables), diagnosis of glial-neuronal tumors (postsurgical variables). CONCLUSIONS: Surgery is a valuable option for children with drug-resistant focal epilepsies which may provide excellent results in a considerable amount of cases. Since results of surgery for epilepsy strongly depend on the presurgical identification of the Epileptogenic Zone, future work should be focused on refinement and implementation of diagnostic strategies.     

Posterior cortex epilepsy secondary to ulegyria: Is it a surgically remediable syndrome?

Purpose: To examine whether surgery is indicated for posterior cortex epilepsy secondary to ulegyria. Patients and methods: Ten patients who underwent surgery for posterior cortex epilepsy with ulegyria and were followed for more than 2 years were included. All patients underwent comprehensive presurgical evaluations. Five patients underwent intracranial electroencephalography (EEG) studies. The posterior cortex including the magnetic resonance imaging (MRI) lesion was resected in all patients. Postoperative follow‐up period was 2–12 (mean 6) years. Results: Nine patients had a history of perinatal distress including asphyxia and prolonged labor. Age at seizure onset was 5–11 years, except one patient. Three patients had visual field defects preoperatively. Ulegyria was unilateral in four patients and bilateral but unilateral‐predominant in six patients. In most of the cases, the lesions were in the posterior cerebral artery area or the watershed area between middle cerebral and posterior cerebral arteries. In four of five patients who underwent intracranial EEG, seizure onset zones extended outside the lesions. Postoperative seizure outcome was Engel's class I in seven cases, and class III in three cases. Three of four patients whose seizure onset zones were not completely resected achieved class I outcome. Four of six patients with bilateral lesions achieved class I outcome. Conclusion: Ulegyria due to perinatal distress is considered to be a major cause of posterior cortex epilepsy. Long‐term postoperative seizure outcome is favorable. Resection of MRI lesion is important for seizure relief. Bilateral lesions should not be excluded from surgical indication. The usefulness of intracranial EEG may be limited.     

Propagation of seizures in a case of lesional mid‐cingulate gyrus epilepsy studied by stereo‐EEG

Little is known about the propagation of seizures arising from the cingulate gyrus, as cingulate coverage with interhemispheric subdural electrodes is usually challenging and incomplete due to inherent anatomical and vascular limitations. We present a case of lesional mid‐cingulate epilepsy confirmed by stereotactically implanted intracranial depth electrodes and subsequent surgical resection. Hypermotor symptomatology was seen during the first seven seconds of seizure onset while the seizure was still confined to the mid‐cingulate gyrus contacts. The patient had brief contralateral clonic movements as seizure propagated to the primary motor cortex. There was a high concordance between the primary propagation contacts, as delineated by intracranial EEG, and the contacts, with higher coherence values in the connectivity matrix. Interestingly, cingulate‐extra‐cingulate connectivity and spread to the primary motor, premotor, and prefrontal cortex was seen preceding spread to other cingulate contacts, of which one was less than 15 mm from the onset contact. This report is one of a few published, documenting propagation of seizures arising from the mid‐cingulate cortex. As illustrated by these data, hypermotor semiology correlated with direct activation of the cingulate cortex. Subsequent seizure propagation activated an extensive extra‐cingulate rather than an intra‐cingulate epileptogenic network. Interestingly, had the region of onset not sampled, the seizure onset would have appeared as non‐localizing widespread rhythms over the fronto‐parietal convexities. Further studies to explore the propagation of seizures arising from the cingulate gyrus and the physiological and pathological connectivity patterns within the cingulate gyrus in humans are needed, preferably using stereotactic implantation. Specific targets to be investigated are also discussed.     

Minimally resective epilepsy surgery in MRI‐negative children

Aim. Performing epilepsy surgery on children with non‐lesional brain MRI often results in large lobar or multilobar resections. The aim of this study was to determine if smaller resections result in a comparable rate of seizure freedom. Methods. We reviewed 25 children who had undergone focal corticectomies restricted to one aspect of a single lobe or the insula at our institution within a 5.5‐year period. Data collected in the comprehensive non‐invasive pre‐surgical evaluation (including scalp video‐EEG, volumetric MRI, functional MRI, EEG source localization, and SPECT and PET), as well as from invasive recordings performed in each patient, was reviewed. Data from each functional modality was identified as convergent or divergent with the epileptogenic zone using image coregistration. Specific biomarkers (from extra‐operative and invasive testing) previously indicated to be indicative of focal epileptogenicity were used to further tailor each resection to an epileptogenic epicentre. Tissue pathology and postoperative outcomes were obtained from all 25 patients. Results. Two years postoperatively, 15/25 (60%) children were seizure‐free, three (12%) experienced >90% reduction in seizure frequency, two (8%) had a 50–90% reduction in seizure frequency, and the remaining five (20%) had no change in seizure burden. There was no significant difference in outcome based on numerous pre‐ and postoperative factors including location of resection, the number of preoperative functional tests providing convergent data, and tissue pathology. Conclusion. In MRI‐negative children with focal epilepsy, an epileptogenic epicentre within a larger epileptogenic zone can be identified when specific biomarkers are recognized on non‐invasive and invasive testing. When such children undergo resection of a small, well‐defined epileptogenic epicentre, favourable outcomes can be achieved.     

Surgery for drug‐resistant tuberous sclerosis complex‐associated epilepsy: who,when, and what

Objective: Tuberous sclerosis complex (TSC) is a multisystem genetic disorder associated with refractory early‐onset epilepsy. Current evidence supports surgery as the intervention most likely to achieve long‐term seizure freedom, but no specific guidelines are available on TSC pre‐surgical workup. This critical review assesses which TSC patients are suitable for surgical treatment, when pre‐surgical evaluation should start, and what degree of surgical resection is optimal for postsurgical outcome. Methods: We searched for publications from 2000 to 2020 in Pubmed and Embase using the terms “tuberous sclerosis,” “epilepsy,” and “epilepsy surgery”. To evaluate postsurgical seizure outcome, we selected only studies with at least one year of follow‐up. Results: Overall, we collected data on 1,026 patients from 34 studies. Age at surgery ranged from one month to 54 years. Mean age at surgery was 8.41 years. Of the diagnostic non‐invasive pre‐surgical tools, MRI and video‐EEG were considered most appropriate. Promising data for epileptogenic tuber detection is provided from invasive SEEG studies. Data on surgery and related outcome were available for 769 patients. Seizure freedom was seen in 64.4% of patients who underwent tuberectomy, 68.9% treated with lobectomy and 65.1% with multilobar resection. The most effective surgical approach was lobectomy, even though more recently tuberectomy associated with the resection of the perituberal area seems to be the best approach to reach seizure freedom. Published postsurgical seizure freedom rates in patients with TSC were between 65% and 75%, but reduced to 48%‐57% over longer follow‐up periods. Early surgery might positively affect neurodevelopmental trajectory in some patients, even though data on cognitive outcome are still to be confirmed with longitudinal studies. Significance: Considering the strong correlation between epilepsy duration and neurocognitive outcome, all patients with TSC ought to be referred early to a dedicated epilepsy centre for individually tailored pre‐surgical evaluation by a multi‐disciplinary epilepsy surgery team.     

Pre-surgical evaluation and surgical outcome of 41 patients with non-lesional neocortical epilepsy.

Pre-surgical evaluation and the surgical treatment of non-lesional neocortical epilepsy is one of the most challenging areas in epilepsy surgery. The aim of this study was to evaluate the surgical outcome and the diagnostic role of ictal scalp electroencephalography (EEG), interictal (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET), and ictal technetium-99m hexamethylpropyleneamine oxime single photon emission tomography ( (99m)Tc-HMPAO SPECT). In 41 non-lesional neocortical epilepsy patients (16 frontal lobe epilepsy, 11 neocortical temporal lobe epilepsy, seven occipital lobe epilepsy, four parietal lobe epilepsy, and three with multifocal onset) who underwent surgical treatment between December 1994 and July 1998, we evaluated the surgical outcome with a follow-up of at least 1 year. The localizing and lateralizing values of ictal scalp EEG, interictal FDG-PET, and ictal SPECT were evaluated in those patients with good surgical outcome. Ictal scalp EEG had the highest diagnostic sensitivity in the localization of epileptogenic foci (69.7% vs. 42.9% for FDG-PET and 33.3% for ictal SPECT; P= 0.027). However, no significant difference was found in the lateralization of the epileptogenic hemisphere among the three modalities (78.8% for ictal scalp EEG, 57.2% for FDG-PET, and 55.5% for ictal SPECT; P= 0.102). During a mean follow-up of 2.77 +/- 1.12 years, 33 (80.5%) showed good surgical outcome (seizure free or seizure reduction >90%), including 16 (39.0%) seizure free patients. Ictal scalp EEG was the most useful diagnostic tool in the localization of epileptogenic foci. Interictal FDG-PET and ictal SPECT were found to be useful as complementary and, sometimes, independent modalities. Many patients with non-lesional neocortical epilepsy would benefit from surgical treatment.     

Epilepsy‐related mortality is low in children: A 30‐year population‐based study in Olmsted County,MN

Purpose: Epilepsy is a common childhood neurologic disorder, affecting 0.5–1% of children. Increased mortality occurs due to progression of underlying disease, seizure‐related accidents, suicide, status epilepticus, aspiration during seizures, and sudden unexplained death in epilepsy (SUDEP). Previous studies show mortality rates of 2.7–6.9 per 1,000 person‐years. Potential risk factors include poor seizure control, intractable epilepsy, status epilepticus, tonic–clonic seizures, mental retardation, and remote symptomatic cause of epilepsy. Few population‐based studies of mortality and SUDEP in childhood‐onset epilepsy have been published. The purpose of this study is to report mortality and SUDEP from a 30‐year population‐based cohort of children with epilepsy. Methods: The Medical Diagnostic Index of the Rochester Epidemiology Project was searched for all codes related to seizure and convulsion in children living in Olmsted County, Minnesota and of ages birth through 17 years from 1980 through 2009. The medical records of these children were reviewed to identify all those with new‐onset epilepsy, and to abstract other baseline and follow‐up information. Potential risk factors including seizure type, epilepsy syndrome, history of status epilepticus, the presence and severity of neurologic impairment, and epilepsy outcome was reviewed. Epilepsy outcome was characterized by seizure frequency, number of antiseizure medications (antiepileptic drugs, AEDs) used, and number of AEDs failed due to lack of efficacy, and epilepsy intractability at 1 year and 2, 3, 5, 10, 15, and 20 years after epilepsy onset. We followed all children through their most recent visit to determine vital status, cause of death, and whether autopsy was performed. Key Findings: From 1980 to 2009, there were 467 children age birth through 17 years diagnosed with epilepsy while residents of Olmsted County, Minnesota, and who had follow‐up beyond the time of epilepsy diagnosis. Children were followed for a median of 7.87 years after the time of diagnosis (range 0.04–29.49 years) for a total of 4558.5 person‐years. Sixteen (3.4%) of the children died, or 3.51 deaths per 1,000 person‐years. Two deaths were epilepsy related (12.5%) for a rate of 0.44 per 1,000 person‐years. One of these children died of probable SUDEP and one died of aspiration during a seizure. The remaining 14 deaths (87.5%) were caused by other complications of underlying disease. Several risk factors for mortality were found, including abnormal cognition, abnormal neurologic examination, structural/metabolic etiology for epilepsy, and poorly controlled epilepsy. Significance: Although mortality in children with epilepsy was higher than what would be expected in the general pediatric population, death occurred significantly more in children with neurologic impairment and poorly controlled epilepsy. Epilepsy‐related death, including SUDEP, was rare and mortality due to epilepsy alone was similar to the expected mortality in the general population (observed deaths = 2, expected deaths = 1.77; standardized mortality ratio 1.13, 95% confidence interval 0.19–3.73, p = 0.86). By contrast, most children died of complications of the underlying neurologic disease or unrelated disease rather than the epilepsy.     

病灶性癫痫的手术治疗及影响其预后的因素分析

目的 探讨病灶性癫痫的手术方法，并分析影响手术预后的一些因素。方法 回顾性地分析自2001年4月～2003年4月之间在我研究所接受手术治疗的所有病灶性癫痫患者的临床资料。33例患者手术后随访时间皆在1年或1年以上。按照Engel疗效分级标准，将其分为效果满意组与不满意组，对术前临床特点、电生理情况、手术方法等因素进行分析比较。结果 手术后效果满意率为73％。下列因素与手术效果有相关性：癫痫患病时间、发作频率以及脑电图发作间期痫性放电是否局限在病灶的脑叶上。另一方面，比较发病时年龄、是否有既发全面强直阵挛性发作以及是否完全切除术中皮层脑电监测(ECoG)为阳性的皮层三个因素，两组间无显著差异。不满意组中，皮质发育不全的患者占多数。结论 对于病灶性癫痫，手术采用病灶与周围致痫灶同时切除的方法，可获得满意的效果。癫痫患病时间、发作频率以及脑电图发作间期痫性放电是否局限在病灶的脑叶上与手术的效果有一定的相关性。     

Multimodality imaging for focus localization in pediatric pharmacoresistant epilepsy.

Multiple structural and functional imaging modalities are available to localize the epileptogenic focus. In pre-surgical evaluation of children with pharmacoresistant epilepsy, investigations with the maximum yield should be considered in order to reduce the complexity of the workup. OBJECTIVE: To determine the extent to which PET, ictal/interictal SPECT and its co-registration with the patient's MRI contributes to correct localization of the epileptogenic focus, surgical intervention and to the post surgical outcome in paediatric patients. METHODS: The study population included children and adolescents with pharmacoresistant epilepsy (n = 50) who underwent preoperative evaluation, surgery and had postoperative follow-up for at least 12 months. Outcome was measured by postoperative seizure frequency using Engel's classification. RESULTS: Thirty-nine patients (78%) became completely seizure free after surgical intervention. The likelihood to benefit from surgical treatment was significantly higher if localization with more imaging modalities (MRI, PET, SPECT) were concordant with respect to the resected brain area (p < 0.01). Preoperative PET examination provided better localizing information in patients with extratemporal epilepsy and/or dysplastic lesions, whereas SPECT was found to be superior to PET in patients with temporal lobe epilepsy and/or tumors (p < 0.05). No significant difference was noted in the surgical outcome in younger or older age group, in children with or without special education needs. CONCLUSION: In paediatric epilepsy pre-surgical evaluation, the combined use of multiple functional imaging modalities for a precise localisation of the epileptogenic focus is worthwhile for both extratemporal and temporal lobe epilepsy, also when EEG and MRI alone are non-contributive, given the potential benefit of complete postoperative seizure control.     

Resection of ictal high-frequency oscillations leads to favorable surgical outcome in pediatric epilepsy

Purpose: Intracranial electroencephalography (EEG) is performed as part of an epilepsy surgery evaluation when noninvasive tests are incongruent or the putative seizure‐onset zone is near eloquent cortex. Determining the seizure‐onset zone using intracranial EEG has been conventionally based on identification of specific ictal patterns with visual inspection. High‐frequency oscillations (HFOs, >80 Hz) have been recognized recently as highly correlated with the epileptogenic zone. However, HFOs can be difficult to detect because of their low amplitude. Therefore, the prevalence of ictal HFOs and their role in localization of epileptogenic zone on intracranial EEG are unknown. Methods: We identified 48 patients who underwent surgical treatment after the surgical evaluation with intracranial EEG, and 44 patients met criteria for this retrospective study. Results were not used in surgical decision making. Intracranial EEG recordings were collected with a sampling rate of 2,000 Hz. Recordings were first inspected visually to determine ictal onset and then analyzed further with time‐frequency analysis. Forty‐one (93%) of 44 patients had ictal HFOs determined with time‐frequency analysis of intracranial EEG. Key Findings: Twenty‐two (54%) of the 41 patients with ictal HFOs had complete resection of HFO regions, regardless of frequency bands. Complete resection of HFOs (n = 22) resulted in a seizure‐free outcome in 18 (82%) of 22 patients, significantly higher than the seizure‐free outcome with incomplete HFO resection (4/19, 21%). Significance: Our study shows that ictal HFOs are commonly found with intracranial EEG in our population largely of children with cortical dysplasia, and have localizing value. The use of ictal HFOs may add more promising information compared to interictal HFOs because of the evidence of ictal propagation and followed by clinical aspect of seizures. Complete resection of HFOs is a favorable prognostic indicator for surgical outcome.     

难治性癫癎MRJ颞极信号特点与癫癎的相关性分析

目的探讨难治性癫癎MRI颞极信号特点与致癎区相关性。方法回顾性分析339例难治性癫癎病人MRI颞极信号特点。根据癫癎发作起始区将研究对象分为颞叶癫癎、额叶癫癎、顶叶癫癎、枕叶癫癎、岛叶癫癎、多脑叶癫癎等6类。结果颞极信号异常187例,颞极信号异常侧别与致癎区侧别一致率达98．93％,颞极信号异常与癫癎类型或致癎区有关（χ2=311．339,P〈0．001）。与颞叶外癫癎比较,颢极信号异常更常见于颞叶癫癎。结论在各类癫癎中均可出现MR／颞极信号异常,但更常见于颞叶癫癎。颞极信号异常侧常与致癎区侧别一致．特别是颞叶癫癎。     

Ictal spitting in non‐dominant temporal lobe epilepsy: an anatomo‐electrophysiological correlation

We report a patient presenting drug‐resistant, non‐dominant temporal lobe epilepsy with ictal spitting and prosopometamorphopsia, both extremely rare semiologies. Second‐phase pre‐surgical monitoring was performed using SEEG due to lesion‐negative imaging and the rare semiology. The seizure onset zone was delimited to the right anterior hippocampus and the temporobasal cortex, with the propagation zone within the entorhinal cortex. Interestingly, direct electrical stimulation to the entorhinal cortex, which was reproduced in a number of trials, evoked spitting without leading to seizures or post‐discharges. After the resection of the epileptogenic zone, the patient remained seizure‐free without AEDs for a follow‐up period of five years (Engel Class 1a). The neuropathology revealed a focal cortical dysplasia type FCD‐Ia. Spectral analysis of intracranial ictal EEG (iEEG) data suggested a possible role of the basal temporal and entorhinal cortex as a necessary node in ictal spitting. [Published with video sequences on www.epilepticdisorders.com ].     

Epileptic seizure semiology in different age groups

Aims. Seizure semiology provides information about the eloquent cortex involved during a seizure and helps to generate a hypothesis regarding the localization of the epileptogenic zone (EZ), a prerequisite for surgical management of epilepsy. We aimed to study the seizure semiology among all different age groups to better characterize semiological changes that occur with age. Methods. We performed a retrospective review of video‐EEG data in paediatric and adult patients admitted to the Epilepsy Monitoring Unit over a three‐year period. Authors independently reviewed and classified the seizure semiology while blinded to clinical, EEG, and neuroimaging data. A total of 270 patients were included in the study. Results. The most frequent EZ in patients who were one month to three years old was undetermined. Focal epilepsy became more frequent in patients older than 10 years. Among patients with focal epilepsy, a posterior quadrant EZ was most frequent in children younger than three years old, a temporal EZ between three and six years old, and a frontal EZ between six and 10 years old. The temporal lobe was the most frequent location for focal EZ in patients older than 18 years. Auras, automotor seizures, and generalized tonic‐clonic seizures were extremely infrequent in patients younger than 10 years old. The youngest patient with auras was 5.7 years old. The youngest patient with automotor seizures was 3.7 years old. We identified only three patients with generalized tonic‐clonic seizures who were younger than 10 years (aged six months, 6.6 years, and nine years, respectively). Patients younger than three years exhibited mostly generalized simple motor seizures and hypomotor seizures. Generalized epileptic spasms, generalized tonic seizures, and generalized clonic seizures were infrequent in patients older than 10 years. Conclusion. Seizure semiology and electroencephalographic changes most likely reflect the maturation of cortical functions.     

Intracranial investigation of a patient with nodular heterotopia and hippocampal sclerosis: dealing with a dual pathology

The pre‐operative assessment and surgical management of patients with dual pathology is challenging. We describe a patient with drug‐resistant focal epilepsy with hippocampal sclerosis and extensive periventricular nodular heterotopia in the same hemisphere. The semiology, scalp EEG, and imaging were divergent, but the presence of focal interictal and ictal epileptic discharges of the putative ictal onset zone resulted in successful localization of the epileptogenic zone. A less aggressive resection was performed based on intracranial EEG recording. The patient has been seizure‐free for three years since resection. Electroclinical hypotheses and challenges in defining the epileptogenic network are discussed.     

A detailed analysis of symptomatic posterior cortex seizure semiology in children younger than seven years

PURPOSE: To analyze the semiology of seizure onset and evolution in young children with posterior cortex epilepsy (PCE), compare this with adult reports, and assess age-related differences. METHODS: We videotaped and analyzed 110 seizures from 18 patients with PCE, aged 3-81 months. All had a good prognosis after posterior epileptogenic zone removal. Ictal events were categorized by behavioral, consciousness, autonomic, and sensory features, as well as motor patterns, which included myoclonic, tonic, clonic, unclassified motor seizures, and epileptic spasm. A time-scaled data sheet was developed to record each epileptic event as onset, very early, early, or late manifestation. RESULTS: Patients had a high seizure frequency with < or =100 attacks/day; one third of them showed a cluster tendency. The mean duration of seizures was 67 s. The most common seizure components were motor manifestations (with myoclonic and tonic seizures), but psychomotor (automotor), hypomotor attacks, and isolated auras also were frequently observed. Clinical seizure spread was frequent; auras and visual sensory signs were difficult to record in this age. Typical phenomena during seizures included behavioral changes, ictal vocalization, smile, flush, head nod, oculomotor features, and late-appearing oral automatisms, whereas hypermotor and secondarily generalized tonic-clonic seizures were not seen. CONCLUSIONS: Our results suggest that PCE in infants and young children is very heterogeneous but shows important age-related features. Compared with adults, children with PCE have shorter but more frequent seizures; they rarely report aura or visual sensory signs, only sporadically develop hypermotor and secondarily generalized tonic-clonic seizures, whereas ictal smile, flush, head nod, and behavioral change are typical features at this age. Because of frequent subtle ictal phenomena, long-term video-EEG monitoring is a useful diagnostic tool with infants and young children with PCE.